Problems with Cycles Baking!
Ok here's what I found. Due to the way your hires model is made you do not have an initial starting point with a basic UV unwrap. So we have to go the cage projection route. Which is the same method you were trying to follow on the video tutorial you posted in the chat.

Attached is the file you sent me, I have manage to produce the normals and AO with no problems on my end. You can try out the blend file below. I have packed a copy of the bake I made. Also to the left of the baking models I have created a GLSL shading model using Blender Internal Materials.

You will need to create nodes holding the texture for Ambient Occlusion and Normals. On the file you will see a green frame and a red one on the node window. The Green one is the node you need to select and make active before baking the Ambient Occlusion. Likewise the Red on is the node which holds the normal texture you need to select before baking.



DOWNLOAD - Here is the file.